The Baltimore County union. [volume] (Towsontown, Md.) 1865-1909, 1887-01-29
Correspondence Baltimore County Union.
SCIENTIFIC MISCELLANY.
w1p1Ne OUT A BIG WASTE spoT.

Correspondence Battimore County Union.
SCIENTIFIC MISCELLANY.
wIPING OUT BIG WASTE SPOT.
Since 1870 the Russian Government has been
engaged in the great work of draining the Pinsk
marshes, in the southwest of Russia, an area very
much larger than Ireland. Several thousand men
have been employed, and up to the present time
about 1000, 900 acres have been reclaimed by the
construction of several thousand miles of bitches
and Of canals so broad as to be navigable for
large barges. OF the reclaimed district about
half is ready for cultivation and the remainder is
in good meadow land and timber-fore Besides
making the canals and bitches, the engineers have
built 17s bridges, bored 577 wells from twenty to
eighty feet deep, and have made survey of TO-
900 square miles of country hitherto unmapped.
This vast enterprise, when completed, will have
effaced one of the toughest bits of savage nature
on the European continent, and is of special en-
cheering and scientific interest.
PHOTOGRAPHY BY PHosPHoREscENcE.
The researches of M. Oh. Zenger have shown
that many substances absorb luminous rays dur
ing the day and at night emit these rays in such
manner as to impress Photographic plates, al
though they may not be perceptible to the eye
He has succeeded not only in photographing the
visible night phosphorescence of Mont Blanc's
summit, but has even secured an impression of an
impression of an invisible midnight landscape
on the terrace of the astronomical observatory at
Prague A plate coated with Balmain's paint,
which becomes self-luminous for considerable
- 10 Erhf 6rsf 0caA IN
the camera for quarter of an hour; and this
plate was then left for some hours in contact with
an ordinary Photographic plate, the result being
very distinct picture. In another experiment,
piece of printed white paper was left in the sun
light, for an hour and then put in the dark in
contact with ordinary sensitive paper, so good
transfer being produced-the black parts In white
and white in black-that the process has since
been adopted for copying bills and note'.
IRISH LIONS
In the Gardens of the Royal Geological Society
of Dublin whose lion breeding has become famous,
no less than I31 lion-cubs have been born since
1857. They were the offspring of nine lionesses
and four lions, lioness having been the mother
of SIS cubs. Of III cubs ITO were reared. The
females greatly exceeded the males, the numbers
being "a to Sc, with the sex of one unrecorded.-
No lion or lioness ever lived in the Gardens for
more than sixteen years, and it is probable that
twelve to fourteen years is the average duration
of lion life. This interesting family traces its
ancestry to pair of lions brought from South
Africa in 1855.
THE SPREAD OF YELLOW FEVER.
somewhat curious theory is that of DR.. Carlos
Finlay, of Havana, who contends that yellow fever
is not transmitted through the air nor by contact.
but by incubation, which is largely performed by
MOSQUITOES These creatures bite victims of the
disease, become infected themselves, and so con-
vey the germs to the blood of other human beings.
To support this view Dr. Finlay mentions that
yellow fever was less prevalent in Havana during
the unusually hot summer of 1885, when mosqui-
tos were scarce, than in the late autumn when the
insects were numerous. He even goes so far as to
conclude that this affection cannot be epidemic
where the tropical mosquito does not abound.
AN AERoNAUTICAL ADVANCE.
A Partisan engineer has successfully tried new
form of air-ship, which is propelled by wings at
tached to the side of the cgar-shaped balloon and
operated by an electric current from battery in
the basket. By this arrangement power is ap-
piled with much less loss than the motor is used
to move the basket. The navigation of a small
balloon has proven so satisfactory that expert
ments will be made with much larger one.
DURABILITY OF SOAKED TIMBER.
1t has been ascertained that timber which has
been fioated in water for considerable time is no
longer liable to the attack of dry-rot. The albu-
men and salts are slowly dissolved out, thus de-
priving the fungus of the nutriment needful for
its development. A French experimenter has
shown that fresh sawdust rots away in a few years
in damp EARTH whereas sawdust from which the
soluble matters have been soaked by water re-
mains unchanged under like circumstances:
MISCELLANEOUS.
Applications of electricity are daily becoming
more varied. Among recent ones are telebarome-
tiers, telethermometers, thermometers and tele-
hydrobarometers, which respectively record, at
distant points, airpressure, heat, steam pressure,
and water stages.
A small river of true ink, with which letters
have been written, is one of the natural curiosi-
ties of Algeria. 1t is formed by the union of two
rivulets, one of which is very strongly impregna-
ted with iron, while the other has imbibed galiic
acid from a peat marsh through which it passes.
year or two ago the great red spot on Jupi-
ter, which has puzzled astronomers since 1877,
was reported to be on the point of becoming in
visible, but it is still so well-defned as to be
very conspicuous object on photograph of the
planet lately taken at the Paris Observatory.
In the Trinity College Botanic Garden, Dublin,
q tree has produced some seedless and coreless
pears from second crop of blossoms, which lack
ed vitality to form core with Seeds
A catalogue of the birds of Italy has been pre-
pared for the Government by Prof. Giglioli, of
Florence. 1t embraces 443 species. Of these,
207 are classed as permanent residents, 9 as of
regular passage, as of irregular passage, Is as
of irregular appearance, so as stragglers, and
as doubtful.
A new rubber-plant has been discovered in
Europe. 1t belongs to the lettuce tribe is scien-
tifcaly known as Sodchus Oleraceus, and is quite
common on the wayside and among dry rubbish
heaps in France. The plants are stepped in car
bon bisulphide, and afterwards boiled in alcohol
and caustic potash, About four and a quarter
per cent of the weight is thus obtained as caout-
chouc of good quality.